> On Jun 30, 2016, at 5:38 PM, Clem Cole <clemc at ccc.com> wrote:
>> ​Hang on that it was not quite that simple. In fact IBM did publish everything because that was what all the PC folks did at the time. As did IBM themselves in their mainframes. Remember when the PC was originally developed, Judge Green has not yet left IBM from its bondage.​ So IBM was very careful in those days to follow industry norms. The PC folks (like Apple, Altair, Cromemco et al) published the schematics and the ROM listings. The OS's and higher level tools were closed but the rest tended to be generally available so IBM followed suit.
But IBM had long stopped publishing source for VM/360 by that point. They were quite aware by the time of ??-DOS that copyright applied to source code.
And by then there were copyright notices being slapped all over BIOS code. I remember seeing it in S-100 systems at the time.